Development of A Decision Support System Using Fuzzy Sets

This paper presents the theoretical basis for the development of a fuzzy decision support system and its implementation on microcomputers. The system utilizes a fuzzy set arithmetic, called fuzzy weighted average (FWA), to evaluate a group of alternatives. The system allows the user to select the criteria (and sub‐criteria if needed) on which the evaluation is to be based. Once the criteria are selected, the user is prompted for ratings (in terms of natural language) of each alternative. The ratings are represented by fuzzy sets in the system. The FWA operation is used to combine all ratings in different stages. For each alternative a final fuzzy set that represents an overall evaluation would be obtained. A simple ranking index model is adopted in the system to select the best alternative. The process is implemented in FORTRAN 77 on a microcomputer. The solution to a selected example problem is presented and discussed.